The following information was provided by Masaya Maeda of the Anacostia Watershed Society.
AWS has decided to conduct a SCA (Stream Corridor Assessment) survey on the Northwest Branch and has already conducted it on a small portion of the stream. We would like to identify environmental problems such as eroding stream banks, inadequate stream buffers, exposed pipes, altered stream channels, fish migration barriers, pipe outfalls, in-stream construction sites and trash dumping locations along the branch. The major findings will be reported appropriately. The data will be also used to raise people's awareness of stream problems and eventually it will be incorporated into WRAS project by State Government.
Survey Date: 4/1/2005
Site 209106 Erosion site
Erosion is a natural process but apparently the erosion occurring in the Anacostia River is too severe.
As the upstream region of the Anacostia River experiences more housing development, stormwater flushes into the river
from the increased impervious surface and consequently annual peak discharge over years is increasing.
Since 1939, the amount of discharge has tripled. See the graph made by AWS using USGS data below the picture.
We need to decrease the amount of this flushing. Incorporation of Low Impact Development (LID) into County code is one of several solutions.
As the upstream portion of NW Branch watershed is developed over years, the impervious surface area increases
and the amount of stormwater flushing into stream increases. We need to reduce this amount.
Site 210105 Exposed pipe
This pipe is in danger of collapse. The pipe could be sewer pipe or natural gas pipe.
It appears to be sewer pipe but there was a sign indicating natural gas pipe in the area.
This case was reported to WSSC asking if this pipe is sewer or not.
In one sense, WSSC and/or Washington Gas are victims of erosion caused by stormwater flushing.
Side View
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Front View
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Site 210106 Unusual condition
Gray water indicates pollution. The source of this small stream
flowing into the main stream is the water from stormwater pipe outfall.
Site 211101 Erosion site
Site 211104 Exposed pipe
Large sewer pipe is exposed. This case was reported to WSSC asking to cover it up for protection.
I am not sure if WSSC has taken any action or not for this site but I believe this should be covered as soon as possible.
We need preventive action. It is too late if WSSC repairs this after it breaks, after millions of gallons of sewage is discharged.
There are good reasons for WSSC to take preventive action. (1) They get a reputation for good work.
(2) The pipe will have a longer lifetime. (3) Protecting pipe before it breaks costs less than replacing pipe after it breaks.
The wooden bar is 2 feet long.
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Scars from stones washed downstream.
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Site 211105 Erosion site
Very long eroded section of the branch. The length is approximately 972 feet.
Pictures show only portion of it.
Site 211107 Erosion site
Approximate length: 898 feet. This picture shows only a portion of the site.
My legs were stuck in the SAND by 1.5 feet at several places several times around this stretch.
It is SAND not mud that caught me by my legs. The fact indicates how erosion is severe.
Usually sand deposits gradually and the riverbed consists with sand is steady enough to walk on it.
But because the erosion is so significant, sedimentation occurs so fast making such loose riverbed with sand.
Then the sand deposition caught my legs.
